Machine for expanding hollow articles



March 21, 1944.

A. E. USHAKOFF Filed May 8, 1941 3 Sheets-Shegat 1 49 13 47\ J 11 4a A "f m w I I 1 ,/19 v M3 igs a 111 //\/Vf/V7'U n 'T AlexisEUsha off Byhi A iy March 21,1944. v USHAKQFE- 2,344,572

MACHINE FOR EXPANDING HOLLOW ARTICLES Filed May 8, 1941 3 Sheets-She et //V7 E/VTUR 39 Alexis EUshakof Patented Mar. 21, 1944 MACHINE FOR EXPANDING HOLLOW ARTICLES Alexis E. Ushakofl, Beverly, Mass, assignor to United Shoe Machinery Corporation, Flemington, N. J., a corporation of New Jersey Application May 8, 1941, Serial No. 392,482

2 Claims.

This invention relates to machines for expanding hollow articles or blanks and is herein illustrated as embodied in a machine for expanding by heat and pressure a thin-walled, hollow cover blank to desired shape and for freezing it in that shape preparatory to placing a heel in the expanded blank and heating it to cause it to shrink about the heel.

In United States Letters Patent No. 2,236,552, granted April 1, 1941, upon an application filed in my name, there is disclosed a hollow heel-cover blank made of macromolecular material in the form of a swollen gel which is capable of stretching somewhat and will shrink by loss of liquid. There are described in said Letters Patent two methods of using such a blank in the cover of a heel. According to one method, referred to therein as the dry method, a block of circular outline is placed in the mouth of the cover blank while the blank is in swollen gel form, and the blank with the block in its mouth is put aside and allowed to shrink, the function of the block being to keep the mouth open and of a desired size. A machine for inserting such a block is disclosed in United States Letters Patent No. 2,296,964, granted September 29, 1942, upon an application filed in my name. Later the blank is expanded by means of heat and pressure and frozen in expanded shape; and finally a heel is placed in the blank, and the blank is heated to cause it to shrink whil at the same time a partial vacuum is created in it so that the shrunken blank will conform exactly to the shape of the heel.

According to the present invention a machine is provided for expanding a hollow article or blank by heat and pressure and freezing it in expanded shape. The illustrated machine has a nozzle over which the mouth of the blank is placed, means for clamping the mouth to the nozzle and for enclosing the blank in a'mold, and means for thereafter forcing first a hot fluid and then a cold fluid into the blank.

Referring to the accompanying drawings,

Fig. 1 is an end elevation of a machine in which the present invention is embodied, part of the casing and the frame being shown in vertical section, and a heel cover blank being shown in place with its mouth over the nozzle of the machine;

Fig. 2 is a front elevation of the machine, part of the casing, frame and cylinder being shown in vertical section;

' Fig.3 is :a detail in vertical section on an ening shown in place; and

Fig. 4 is a detail also in vertical section and on an enlarged scale showing the nozzle and the mold, there being in the mold an expanded heel cover blank.

The purpose of the machine, as has been stated, is to expand a hollow blank by means of heat and pressure and to freeze it in expanded shape; and, before describing the machine in detail, a general description of its mode of operation will be given. The blank Hill has a comparatively large, circular mouth and has extending from its closed end a slender, solid projection 200 which was formed in the sprue of the molding machine in which the blank was made. In the operation of the machine a blank is placed with its mouth over a nozzle 1, said mouth having been made of such a size and shape that it fits the nozzle fairly closely. The blank is centered to an extent, if necessary, in a manner presently to be described, by means of a vertically slidable, slender tube 9 (Fig, 1); and then a hollow mold, which comprises an open-ended portion H and a bottom I3, is brought down into the position shown in Fig. 4 in which the wall around the mouth of the blank I00 is clamped between the tapered outer surface of the nozzle 1 and the tapered inner surface of the hollow mold l l in such manner as to form an air-tight joint, the tapers on the mold and on the nozzle being so constructed as to limit further downward movement of the mold. With the blank so held, hot air, forced in through a conduit I5, flows out through a pipe 11 and thence through a valve, hereinafter described, whereby the outflow of air may be restricted as desired to control the pressure of the hot air in the blank. This compressed hot air heats the blank and expands it against the inside of the mold as shown in Fig. 4. As soon as the blank has thus been expanded, the supply of hot air is cut oil, and cold air, which may be at room temperature, is forced through a conduit 19 and through connected ports 2i in the nozzle 1 into the blank to freeze it, said cold air flowing out through the same conduit ll through which the hot air flowed out. The operation on the blank is now complete, the mold is raised and the blank is removed. The general mode of operation of the machine having been thus briefly outlined, a detailed description of the machine will now be given.

Referring to Figs. 3 and 4, the nozzle 5 is a block circular in cross section and has extending vertically through it a bore 29 of larger diameter than that of the hot air conduit [5. It also has vertical ports 2| which are connected by a port 23, the latter being in communication with the cold air conduit I9. The nozzle is fastened to the upper flanged end of a generally spool-shaped member 25 by screws 21, the lower flanged end of the member 25 being fastened by screws 29 to a heavy stationary plate 3| (Figs. 1 and 2) which is' supported on the top of a frame, said frame comprising uprights 33 and cross pieces 35. Referring again to Figs. 3 and 4, the receiv-- ing end of the conduit ll, through which the hot :air and the cold air flow out, is threaded into a hollow boss on one side of the spool-shaped member 25; and directly opposite there is threaded into another hollow boss a conduit 31 which leads to a pressure gage 39 (Figs. 1 and 9.)

The open-ended portion II of the hollow mold has at its lower end a flange which fits into a rabbet on the inner wall of an annular supporting member 4|, said flange being clamped to the supporting member by a ring 43 and nuts 35 threaded on four small upright rods 41, the lower ends of which pass through holes in the ring and are threaded into the annular member 4 I. The openended portion H of the mold is preferably made of metal. The bottom 13 may be a thick sheet or plate of transparent resin square in outline and having large holes through which the slender rods 4'! pass. The bottom of the mold i held down against the smaller end of the open-ended portion II by four compression springs 49 which surround the slender rods 41, the lower end of the springs resting upon washers 5! and the upper ends being in contact with nuts 53 which are threaded on the rods 47. Resting upon the four nuts 53 is a thin plate 55 which is fastened in place by nuts 57. The thin plate has in its center 'a bore of larger diameter than that of the slender tube 9, the tube extending through this bore and through a bore in the bottom [3 of the mold. When the mold is in raised position (Figs. 1 and 2) the tube 9 is suspended from the thin plate 55 by its head which is too large to pass through the bore in this plate.

The blank I05, as has been explained, was in the form of a swollen gel when it was mad and was allowed to shrink, a block of proper shape having been first placed in its mouth to hold the mouth open. During this shrinking, the blank sometimes becomes somewhat deformed so that the slender projection 250 is off center. The purpose of the tube 9 is to facilitate centering the blank approximately when it is in the position shown in Fig. 1 after having been placed with its mouth over the nozzle 1 and'before the mold has been moved down over it. To accomplish this, the blank is placed with its mouth over the nozzle, then the lower end of the pipe 9 is placed over the projection 208, the bottom N3 of the mold being slid horizontally to permit this, and finally the bottom is slid back into proper position, the sliding of the bottom being permitted by reason of the fact that the holes through which the rods 4'! pass are enlarged and that the bottom is yieldingly held in place by the springs 45. The springs 49 obviously do not exert a very great pressure upon the plate or bottom 35 of the mold, since the plate may readily be slid horizontally to permit positioning of the pipe 9; and, by

. manipulating the valve H3 to regulate the pressure of compressed hot air, said pressure may be caused to lift the bottom 53 slightly, if desired, during the momentary expanding of the of three rods 59 which are vertically slidable (Fig. 2) in bores formed in the stationary plate 3! and in upwardly projecting bosses on said plate, the lower ends of said rods being fastened to a circular plate Bil which is carried at the upper end of a piston rod 6|, the lower end of said rod carrying a piston, indicated as a whole at 63, said piston being adapted to reciprocate in a vertical cylinder 65 which is suspended rigidly from the stationary plate 3! by means of vertical tie-rods 61. When a blank to be expanded has been placed in position as shown in Fig. 1, compressed air causes the piston 63 to descend and pull down and that a blank I00 has been put in place as shown in Fig. 1, the machine is operated by first swinging a hand-lever 69 (Fig. 2) in one direction which admits compressed air to the top of the cylinder 65 and exhausts air from the bottom of the cylinder so that the mold is brought down over the blank. After this there is pushed down a button H at the upper end of a valve rod 13, whereupon compressed hot air is forced into the blank to expand it. Next there is pushed down a button 75 at the upper end of a valve rod 77, whereupon compressed, unheated or cool air is forced into the blank to freeze it in its expanded shape; and finally the hand-lever 59 is swung back to its original position, whereupon the piston raises the mold structure to the position shown in Figs. 1 and 2.

Two conduits '59, fit for compressed air connect respectively the upperand the lower ends of the cylinder 55 with a valv 'rnechanism of commercial form, the details of construction of which form no part of the present invention. This mechanism comprises a casing 53 to which compressed air is supplied continuously through a conduit and in th casing are suitable valves controlled by the handle 69 which has been referred to above. When the handle is at one limit of its swinging movement, compressed air flows through the conduit 8! to the bottom of the cylinder, the top of the cylinder being exhausted through the conduit 19; and when the handle is swung to the other limit of its movement, the reverse takes place. The exhaust, whether from the top or from the bottom of the cylinder,

emerges from the casing 33 through a conduit 8! and is delivered through a T 39 and a conduit 91 into the upper end of a mufiler The compressed air which is forced into the blank is supplied through a conduit 55 and passes into a horizontal conduit 91. Leading from the latter conduit are two conduits, one for air which is to be heated and one for cold air. The conduit for air which is to be heated has in it a valve 99 which is normally held closed but may be opened by pushing down on the button H in the upper end of the valve rod '53. The conduit for air which is not to be heated has in it a similar valve HH which may be opened by pushing down the button 15 at the upper end of the valve rod TI. The lower ends of the valve rods 73, 1! are connected with their respective valves in the-same manner, the connection of the rod 1'! with its valve being shown in Fig. 1 wherein said rod is pivoted to the outer end of an arm which rests upon the top of the stem of the valve, the inner end of the arm being pivoted to a stationary bracket I93. When the valve 99 is opened, compressed air, which is supplied from the conduit 95, flows through a conduit I95 into the bottom of a heater It], then up through the heater and out of its upper end through a conduit I09 which leads into the bottom of a second heater I I I, then up through that heater and out of its upper end into the conduit I5 which (Fig. 3) terminates in the nozzle 1. Referring now (Figs. 1 and 2) to the conduit 95 through which compressed air is supplied for heating and expanding and then cooling the blank, if the button I5 at the upper end of the valve rod I1 is pushed down to open the valve I9 I, the unheated air passes up through the conduit I9 which leads (Fig. 3) into the nozzle. As has been noted, both the hot air and the cool air flow out of the blank through the conduit I'I. Referring now to Fig. 2, this conduit leads down into the same T 89 into which the exhaust conduit of the cylinder 65 leads. In order to be able to raise and lower the pressure of the air in the blank, this conduit IT has in it a valve II3 which may be opened more or less as may be desired by turning a hand wheel I I5, the pressure being indicated by the pressure gage 39. In order to prevent the exhaust from the cylinder 65 through the conduit 81 from flowing up through the conduit I1 and thereby interiering with the outflow of air from the blank, a check valve I I! is located in the conduit II. The air heaters I01 and III may be of any suitable type, those shown containing electrical heating units.

The operation of the machine is briefly as follows. With the parts of the machine in the positions shown in Figs. 1 and 2, the operator places the mouth of a blank I99 over the nozzle 1 with the lower end of the tube 9 over the projection 290, as shown in Fig. 1. He then swings the hand-lever 69 in one direction to cause the mold to be brought down into the position shown in Fig. 4- to enclose the blank and to clamp its mouth to the nozzle 1. Next he pushes down the button .'I to cause hot compressed air or other fluid to be admitted to the interior of the blank to expand it against the interior of the mold as shown in Fig. 4, the fluid flowing out through the conduit II, this outflow having been restricted to give the desired pressure in the blank by adjustment of the valve H3 in said conduit. Next he releases the button II and immediately pushes down the button I5 to cause cold or unheated fluid to be admitted to the interior of the blank to freeze it in expanded shape, said fluid flowing out through the same conduit II as did the hot fluid. The button I5 is then released, and the hand-lever 69 is manipulated to return the parts of the machine to the positions shown in Figs. 1 and 2, whereupon the expanded and frozen blank, which usually remains with the mold, is removed.

Although the invention has been set forth as embodied in a particular machine, it should be understood that the invention is not limited in the scope of its application to the particular machine which has been shown and described.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. A machine for expanding a hollow blank having a mouth, said machine having in combination a tapered nozzle over which the mouth of the blank is placed, a mold-support reciprocable toward and from the nozzle and normally held away from the nozzle a distance greater than the height of the blank to permit the blank to be placed with its mouth over the nozzle, a mold carried by said mold-support, said mold having a tapered mouth to fit over the tapered nozzle, an actuator for the mold-support located upon the side of the nozzle opposite to that upon which the mold support is located, means for moving the actuator away from the nozzle to cause the mold to enclose the blank and to clamp the mouth of the blank to the nozzle, and means for admitting fluid under pressure through the nozzle to expandthe blank.

2. A machine for expanding a hollow blank having a mouth, said machine having in combination a nozzle to receive the mouth of the blank, a mold adapted to clamp the mouth of the blank to the nozzle, said mold comprising a hollow member the mouth of which extends over the nozzle, a bottom member extending over and normally closing that end of the hollow member remote from the nozzle, yielding means tending at all times to hold the bottom member in contact with the said end of the hollow member of the mold to close the opening in said end, and means for admitting fluid under pressure through the nozzle.

ALEXIS E. USHAKOFF. 

